Method and related apparatus for cutting a product from a sheet material

ABSTRACT

A method of cutting a product of a predetermined shape from a sheet material ( 1 ) by firstly supporting a sheet material in a first position by a first support means ( 2 ) whereafter she sheet ( 1 ) may be cut through by moving a line type cutter ( 7 ) relative to the sheet material on a line or lines to define part of the predetermined shape. The sheet material may then be supported in a second position (whether by the first support means or another support means ( 2   a   , 2   b )) and again cut by moving a line type cutter relative to the sheet material on a line or lines to define the remaining perimeter of the predetermined shape, to thereby cut the predetermined shape from the sheet material. In the second position the sheet material is provided with upward support to support the predetermined shape to be cut from the sheet material and wherein in the second position the or another support means includes a through cut commensurate to the line or lines to define the remaining perimeter of the predetermined shape.

FIELD OF THE INVENTION

The present invention relates to a method and related apparatus forcutting a product from a sheet material.

BACKGROUND OF INVENTION

The cutting of predetermined shapes from a sheet material may beachieved by using a laser or fluid jet or similar. When using a fluidjet to cut such material is it very difficult to control the depth ofcut accurately. Indeed normally the material is cut all the way throughits entire thickness with the jet passing through the material from oneside another. The sheet material is normally secured by a fixture whichsupports the sheet material to allow for the jet to pass from one sideto the other without the jet being unnecessarily disbursed or impingingon other parts of the fixture. By way of example, a fixture may hold asheet material above a water filled tank and from the other side ofwhich the jet impinges onto the sheet to cut through the sheetthereafter being directed into the water filter tank to disburse anyremaining jet energy.

When it comes to methods to hold the sheet material, limitations ariseespecially if the jet used to cut the material may, once passed throughthe material still has sufficient energy to cause damage to the portionsof the fixture on the other side of the sheet material. Whilst the sheetmaterial may be held at its perimeter region allowing for a clearpassage of cutting fluid to pass through the sheet material and into thetank beneath, the product cut from the sheet material will subsequentlyfall into the tank of water from which it will need to be removed. Theproduct cut from the sheet material floating around in the tank maybecome damaged from subsequent jet action being directed into the tankof water. For cutting of small squares or rectangles for example themethod of fixing the sheet is of real concern as the jet needs to beable to pass freely through the sheet and then passed the fixture, intothe water tank without damaging the fixture. The fixture mustsimultaneously be designed to support the parts once separated by thecutting action. Where the fixture is able to maintain support to thesheet by extending below and inwardly from the perimeter of the sheet,the cutting of a product from the sheet material is not a problem.However as soon as a product to be cut is to be generated entirelyinwardly from the perimeter of the sheet, support by the fixture to thatproduct to be removed from the sheet can no longer occur where the sheetand the fixture remain in a fixed relationship to each other during thecutting process.

Accordingly without providing a hole in the fixture about the product tobe cut from the sheet, but to remain supported by the fixture thecutting process can not be performed without the jet also impinging onpart of the fixture itself. To avoid the jet impinging on the fixtureitself in such a relationship, a hole in the fixture of a greater sizeto the product to be cut from the sheet must be provided which, once theproduct is entirely cut from the sheet will result in the product fromfalling through and away from the fixture.

For certain cutting procedures it is also imperative that a high degreeof accuracy of the items cut from a sheet is achieved to within veryclose tolerances. This is particularly so in relation to the cuttingitems from a sheet to be used in circuit board or other electronic typeapplications. Therefore in mounting a sheet for cutting it is desirablefor the sheet to remain in a relationship to the cutting device whereinthe relationship remains constant such that during a computer controlledcutting of the sheet, no margin of error can be introduced between therelative positioning of the cutting device and sheet as a result of forexample the movement of the sheet between different cutting stations.

Accordingly it is an object of the present invention to provide a methodand related apparatus for cutting a product from a sheet material whichovercomes the abovementioned difficulties or which will at least providethe public with a useful choice.

BRIEF DESCRIPTION OF THE INVENTION

In a further aspect the present invention consists in a method ofcutting a product from a sheet material as herein described and withreference to the accompanying drawings.

This invention may also be said broadly to consist in the parts,elements and features referred to or indicated in the specification ofthe application, individually or collectively, and any or allcombinations of any two or more of said parts, elements or features, andwhere specific integers are mentioned herein which have knownequivalents in the art to which this invention relates, such knownequivalents are deemed to be incorporated herein as if individually setforth.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective and cut away view of an apparatus of the presentinvention provided for cutting a product from a sheet material,

FIG. 2 is a plan view of two support means both being in the form ofsupport tables and a multi-head cutting unit, showing an example of apattern of cuts provided through the two supporting support means toproduce a product by cutting, of squares or rectangles from a sheetmaterial,

FIG. 3 is a plan view of the path of travel of the multi-head cuttingunit of FIG. 2 through the slots provided in both support means,

FIG. 4 is a perspective view of a multi-head cutting unit and the twosupport means as shown in FIG. 2,

FIG. 5 is a plan view of two cutting tables,

FIG. 6 is a perspective view of an alterative step up of apparatus ofthe present invention, without the sheet material being shown,

FIG. 7 is a perspective view of the step up of FIG. 6 but wherein asheet material is provided to a support means,

FIG. 8 illustrates the cutting means ready to commence cutting of thesheet material supported by the support means wherein movement in the Xdirection is provided by the support means along the rails and movementin the Y direction is provided by the cutting head,

FIG. 9 is a plan view illustrating the path cut by the cutting means inthe first cutting phase,

FIG. 10 is a perspective view of the apparatus of FIG. 6 wherein asecond support means this time a support table is brought into anunderlying relationship with the sheet material immediately prior to andduring the cutting of the sheet material in the second phase,

FIG. 11 is a plan view of FIG. 10 illustrating the path cut by thecutting means during the second phase,

FIG. 12 illustrates the support table in a retracted condition fromunderlying the sheet material but where the pieces cut from the sheetmaterial have been removed and still remain supported on the supporttable,

FIG. 13 is a perspective view after the entire cutting procedure hasbeen completed illustrating the items cut from the sheet material aswell as the wastage portion of the sheet material.

DETAILED DESCRIPTION OF THE INVENTION

The present invention allows for a shape to be cut from a sheet materialby using a line type cutting apparatus such as for example an abrasivefluid jet, laser, wire spark erosion, flame cutting or similar. Withreference to FIG. 1, the sheet 1 is able to be mounted by a supportmeans 2 which provides a support to the sheet 1 at least whilst it isbeing subjected to the cutting action by the cutting means. In thisexample the support is from below the sheet. Most preferably the supportmeans is substantially horizontal and the cutting means is directed fromabove the support means and directs its jet or beam or flame downwardlyand into a water filled container 3 which contains water 4 to disbursethe energy of the jet 5. The support means 2 preferably locates thesheet 1 securely thereon so that it does not move relative to thesupport means at least during the process of cutting the material. Thesheet 1 may be secured by a vacuum action, magnetic fastening or by amechanical fastening means or the like. Alternative fastening means maybe utilised. The support means 2 includes a support region at which thesheet is supported and wherein provided through the support means 2,there is a slot 6 which is at least commensurate with the cut that isprovided through the sheet by the cutting means 7. The cutting means 7moves relative to the sheet 1 (and the support means 2) and preferablymoves along X, Y co-ordinates. Angled travel of the cutting means 7 iswithin the scope of the invention and indeed polar co-ordinate movementmay also be utilised. The cut 8 of the sheet 1 is along a line whichcorresponds to the slot 6 provided through the support means 2. The slot6 may be slightly larger in width than the width of cut provided by thejet of the cutting means 7 through the sheet 1. In this way, the supportmeans 2 does not become damaged by the action of the jet passing throughthe sheet 1 and slot 6 since the path of cutting of the sheet 1 iscommensurate to the slot 6 provided through the support means 2.

In order to cut objects from the sheet material where the entireperimeter of the cut object is within the boundaries of the sheet 1, amulti-step cutting process is employed by the present invention. In afirst step, a first portion of the perimeter of the shape to be cut fromthe sheet is defined by cutting along the perimeter portion (whether 1or more separate lines) by the jet when the sheet is supported by thesupport means in a first position. In this first position the slot 6 ofthe support means 2 extends to be commensurate with that portion of theperimeter of the shape to be cut by the jet. The sheet 1 is then movedto a second position where the blank then overlies a slot to becommensurate with the remaining portion of the perimeter of the shape tobe cut from the sheet. In this subsequent position, the previously cutperimeter portion of the shape does not require to be commensurate withany slot of the second support region. Whilst in the most preferred formonly two cutting steps are provided, first to define a first cut or cutsof a first portion of the perimeter and a second to define a subsequentcut or cuts to define the remaining perimeter portion of the shape to becut from the blank, it is to be appreciated that more than two cuttingsteps may also achieve the same result. However for efficiency twocutting steps are sufficient.

In the most preferred form after the first cutting step the blank 1 isactually moved to a second support means, being a support tableproviding the slots to allow the jet to pass therethrough during theprocess of cutting the remainder of the perimeter of the shapes from theblank.

With reference to FIG. 2, there is shown an arrangement where twosupport means (2A, 2B) are provided with slots to produce by the use offour cutting means 7 moving as a unit 9, a total of 36 substantiallysquare items and 12 rectangular items from the sheet material. In FIG.2, the sheet material is not shown to be mounted. However in operation,the unit 9 is moved to cut the sheet material when mounted on the firstsupport means 2A in the Y direction. In FIGS. 2 and 3, there is shown tobe four Y direction cuts to be made by each of the cutting means 7 inthe blank. The blank is then transferred to the support table 2B. Whenmounted on the support table 2B, each of the cutting means 7 operate tocut the sheet in the X direction. Again four cuts in the X direction aremade to each traverse across the cuts (preferably at 90°) made duringthe first cutting process and thereby separate nine substantially squareshaped items from the blank wherein the cut items remain supported bythe support table 2B after having been completely cut.

In moving to cut along the four lines in the X direction, each cuttingmeans 7 is firstly advanced along a feeder slot 10 extending in the Ydirection. With reference to FIG. 3, the path moved by the jet is shown,in where for example the jet remains continuously operating during themovement along the lines to cut the sheet.

With reference to FIG. 5, it will be appreciated that otherpredetermined shapes such as for example a circular shape can be cutfrom a sheet by first placing a sheet on the first support means 2A andfor two cutting means 7 to cut along the curve lines as shown whereafterthe sheet can be moved and placed on the support table 2B whereafter thetwo cutting means 7 can cut along the two curved lines as shown on thesupport means 2B to thereby complete a cutting of a perimeter of theitems to be removed from the blank.

Alternative to using two different support means, the sheet may berepositioned on the same support means, utilising the same slots. In theexample as shown in FIG. 5, the support means 2A may be utilised forcutting the product from the sheet wherein a first cutting step thesheet is positioned over the curved shapes to be cut substantially alongthis line, and wherein after the sheet is rotated about Z-Z it issubsequently cut in the second cutting step again along the curved linesbut this time thereby defining the remainder of the perimeter of theshape to be cut from the sheet.

By following the cutting pattern as for example shown in FIG. 3 or 5 orsimilar, the design of the support means can be such that the jet willnot damage the support means during the cutting process. The pre-cutsubstrate between the first and second cutting steps will still be rigidenough but after the first cutting step, it can be transported to besecured in the second position (whether on the same or a differentsupport means) for the final cutting process.

The sheet may alternatively be supported during the first cuttingprocess by a support means which need not necessarily provide slotsbeneath the lines to be cut in the sheet material, since the cutsprovided during the first cutting process will not remove any of theproduct from the sheet material. However the support provided withcommensurate slots during the cutting process, may reduce thevibrational effect by the cutting means transmitted to the sheetmaterial. During the final cutting process the sheet material ispreferably entirely supported by the supporting regions save for wherethe slots through the supporting means of the second supporting regionare provided.

In FIGS. 1-13, there is shown an alternative arrangement of theapparatus of the present invention for cutting of discrete items fromthe sheet material. A first support means 102A is provided on a slidingX axis which moves the support means in the X direction relative to thecutting means. Such movement is preferably numerically controlled and isable to accurately control the positioning of the sheet material in theX direction relative to the cutting means 107. The cutting means 107itself is moveable in a Y direction to control the Y direction cuttingthe sheet material. A support table 102B is provided to also be able tomove in the X direction but also has a movement component in a Zdirection.

In use a sheet material is placed on the first support means 102A as forexample shown in FIG. 7. This first support means includes a singleopening 150 which is provided below the regions to be cut in the firstcutting procedure by the cutting means 107. The sheet material isperimeter supported by the support means and is most preferably mountedon the support means by locating pins 151 which extend through aperturesin the sheet material to thereby accurately and securely locate thesheet material with the support means. Whilst the opening 150 is shownto be provided within the perimeter of the support means 102 a,alternatively the opening 150 may be a rebate in the substantiallyrectangular form of the support means and hence a form to define part ofthe perimeter shape thereof.

During cutting of the sheet in the first cutting procedure, a path asfor example shown in FIG. 9 may be defined. Accurate cuts in a Ydirection are provided in this first cutting procedure and to providecontinuation between the X direction cuts, accelerated cutting of thesheet material in the X direction may be provided. After the firstcutting procedure to define the path as for example shown in FIG. 9, noseparated elements from the sheet material are defined and hence thesheet material still remains intact save for those portions which havebeen cut away along the path of cutting by the cutting means.

In preparation for the second cutting procedure the support table 102 bis moved to become positioned beneath the sheet material. However thesheet material still remains, and in addition, supported by the firstsupport means 102 a. The support table 102 b merely positions itself tobe located beneath the opening 150 of the first support means 102 a. Thesupport table is able to move in the X direction and in the Z directionso as to be positioned accordingly. The support table provides slotsthere through which are commensurate with the path to be cut by thecutting means through the sheet material in the second cuttingprocedure. The path to be cut during the second cutting procedure is asfor example shown in FIG. 11 wherein accurate cuts are made in the Xdirection and accelerated cuts may be made in the Y direction in movingbetween the X direction cuts. The slot or slots in the support means aresubstantially commensurate with the path or paths cut by the cuttingmeans during the second cutting procedure. Since the X direction cutstraverse against the Y direction cuts made in the first cuttingprocedure, separate elements are cut from the sheet material and as forexample shown in FIG. 12 or FIG. 13, such separated elements aresubstantially square or rectangular shapes. These remain upwardlysupported by the support table 102 b.

The benefit of maintaining the sheet material on the first support meansfor both the first and second cutting procedure is that no transfer ofthe sheet material is required to be made to a different support means.The support table merely positions itself to be relied upon inconjunction with the first support means for the second cuttingprocedure whilst the sheet material still remains in a fixedrelationship relative to the first support means. With the provision ofsuch location means as the support pins the sheet material can remainaccurately positioned relative to the cutting means thereby ensuringthat an accurate repeat of cut is able to be provided.

1-35. (canceled)
 36. A method of cutting a product of a predeterminedshape from a sheet material comprising; supporting a sheet material by afirst support means, cutting through said sheet material by moving aline type cutter relative to said sheet material on a line or lines todefine part of the perimeter of said predetermined shape whilst saidsheet material remains supported by said first support means inrelationship, moving said sheet material, remaining in a fixedrelationship with said first support means to a condition supportingsaid sheet material relative to and onto a support table, whilst saidsheet material remains in a fixed relationship with said first supportmeans, cutting through said sheet material moving a line type cutterrelative to said sheet material on a line or lines to define theremaining perimeter of said predetermined shape to thereby cut saidshape from said sheet material whilst said sheet material is supportedon said support table in a fixed relationship, wherein said supporttable includes a through cut extending therethrough commensurate to theline or lines cut to define said remaining perimeter, said support tableproviding support to said predetermined shape after having been cut fromsaid sheet material, and wherein said first support means provides nosupporting regions below where the line or lines to be cut during saidfirst mentioned cutting procedure are to be made.
 37. A method asclaimed in claim 36 wherein sheet material remains supported by saidfirst support means during the cutting of the remaining perimeter.
 38. Amethod as claimed in claim 36 wherein said support means provides upwardsupport to said sheet material at least at regions of the downwardlyfacing surface of said sheet material not to be cut during said firstmentioned cutting procedure.
 39. A method as claimed in claim 36 whereinsaid support means provides upward support to said sheet material atregions of the downwardly facing surface of said sheet material not tobe cut during said first mentioned cutting procedure.
 40. A method asclaimed in claim 36 wherein said support means provides upward supportto said sheet material at regions of the downwardly facing surface ofsaid sheet material not to be cut during said second mentioned cuttingprocedure.
 41. A method as claimed in claim 36 wherein said supportmeans provides upward support to said sheet material at the perimeterregion only of the downwardly facing surface of said sheet material. 42.A method as claimed in claim 36 wherein said support table is positionedfor said second mentioned cutting procedure in an upwardly supportingcondition to said sheet material to provide upward support to at leastthat part of said sheet material from where said predetermined shapeswill be generated.
 43. A method as claimed in claim 36 wherein sheetmaterial is engaged to said support means during at least said firstmentioned cutting procedure by at least two location pins extendingthrough said sheet material.
 44. A method as claimed in claim 36 whereinduring cutting of said sheet material on a line or lines to define partof the perimeter of said predetermined shape said support means providessupport to said sheet material on the support means facing surface ofsaid sheet material immediately adjacent the said line or lines are cut.45. A method as claimed in claim 36 wherein said second mentionedcutting procedure moves said cutting means to generate a line cut ofsaid sheet material to strike the line of cut generated during saidfirst mentioned cutting procedure.
 46. A method as claimed in claim 36wherein said second mentioned cutting procedure moves said cutting meansto generate at least two parallel lines of cut of said sheet materialwhich each traverse across at least two parallel lines of cut generatedduring said first mentioned cutting procedure.
 47. A method as claimedin claim 36 wherein said second mentioned cutting procedure moves saidcutting means to generate at least two parallel lines of cut of saidsheet material which each extend across at least two parallel lines ofcut generated during said first mentioned cutting procedure at rightangles.
 48. A method of cutting a product of a predetermined shape froma sheet material comprising a) supporting said sheet material by asupport means in a position engaging regions of said sheet materialnon-commensurate with a preliminary line or lines to be cut through saidsheet material, b) cutting said sheet by a line type cutter on apreliminary line or lines to define a part of the perimeter of saidpredetermined shape whilst remaining in support by said support means c)moving sheet material and said means to support supporting said sheetmaterial relative to another means of support to thereby provide upwardsupport to said major surface of said sheet material by said anothermeans to support to overly a non upwardly supporting region of saidanother means to support commensurate at least with a subsequent line orlines to be cut through said sheet material; d) cutting said sheetmaterial by a line type cutter on a said subsequent line or lines todefine further perimeter of said predetermined shape until a product ofsaid predetermined shape is separated from said sheet material, whereinsaid upward support to said major surface of said sheet by said oranother support means, supports said predetermined shape once separatedfrom said sheet, and wherein said means to support and said anothermeans to support are brought into register with each other prior tocutting of step (c).
 49. A method as claimed in claim 48 wherein saidproduct of predetermined shape is separated from said sheet materialwithout repeating steps (c) and (d).
 50. A method as claimed in claim 48wherein a plurality of product of predetermined shape are cut from saidsheet material by cutting in said first mentioned cutting step aplurality of discrete lines in said sheet material and cutting in saidsecond mentioned cutting step at least one line in said sheet materialto separate said products of predetermined shape.
 51. A method asclaimed in claim 48 wherein a plurality of product are cut from saidsheet material by cutting in said first mentioned cutting step a line insaid sheet material and cutting in said second mentioned cutting step atplurality of discrete lines in said sheet material to separate saidproducts of predetermined shape.
 52. A method as claimed in claim 48wherein said or another support means is a support table and said nonupwardly supporting region of said support table are slots there throughcommensurate at least with said subsequent line or lines to be cutthrough said sheet material.
 53. A method as claimed in claim 52 whereinsaid support table is separate from said first mentioned support means.54. A method as claimed in claim 48 wherein the first mentioned supportmeans provides support to at least part of the perimeter only of saidsheet material.
 55. An apparatus for cutting a product having aperimeter of a predetermined shape from a sheet material comprising; afirst support means to receive said sheet material wherein no support isprovided by said first support means at least along a line commensurateto a portion of the perimeter shape of said product to be cut in a firstcutting procedure a second support means including a support region tosupport said sheet material in a condition having said portion of saidperimeter shape cut, said second support means including a slot or slotscut there through commensurate to the remaining portion of the perimetershape of said sheet material to be cut in a second cutting procedure atleast one line type cutting means movable relative to said to sheetmaterial to cut through said sheet material during said first and secondcutting procedure and to pass also through said second support meansduring a second cutting procedure means to allow registration of thelocation of said first support means with said second support means toprovide accurate positioning of said support region in support of saidsheet material.
 56. An apparatus as claimed in claim 55 wherein saidfirst mentioned support means provides upward support to said sheetmaterial at least at regions of the downwardly facing surface of saidsheet material not to be cut during said first cutting procedure.
 57. Anapparatus as claimed in claim 55 wherein said first mentioned supportmeans provides upward support to said sheet material at regions of thedownwardly facing surface of said sheet material not to be cut duringsaid first cutting procedure.
 58. An apparatus as claimed in claim 55wherein said first mentioned support means provides upward support tosaid sheet material at regions of the downwardly facing surface of saidsheet material not to be cut during said second cutting procedure. 59.An apparatus as claimed in claim 55 wherein said first mentioned supportmeans provides upward support to said sheet material at the perimeterregion of the downwardly facing surface of said sheet material only. 60.An apparatus as claimed in claim 55 wherein said second support regionis positioned for said second cutting procedure in an upwardlysupporting condition to said sheet material to provide upward support toat least that part of said sheet material from where said predeterminedshapes will be generated.
 61. An apparatus as claimed in claim 55wherein said support means include at least two location pins to extendthrough said sheet material.
 62. An apparatus as claimed in claim 61wherein said first mentioned first means includes a slot or slots cutthere through commensurate to said portion of the perimeter shape ofsaid product to be cut in a first cutting procedure.
 63. An apparatus asclaimed in claim 62 wherein each said slots of said first mentionedsupport means extend from a first end thereof at a perimeter edge ofsaid support means to a second end thereof inward of the perimeter ofsaid support means.
 64. An apparatus as claimed in claim 55 wherein eachsaid slots of said second mentioned support means extend from a firstend thereof from a feeder slot of said second mentioned support means toa second end thereof inward of the perimeter of said support means saidfeeder slot extending at a first end thereof at a perimeter edge of saidsecond mentioned support means and at a second end inward of theperimeter of said second mentioned support means.
 65. A method ofcutting a product of a predetermined shape from a sheet materialcomprising; supporting a sheet material in a first position by a firstsupport means in a fixed relationship therewith cutting through saidsheet material by moving a line type cutter relative to said sheetmaterial on a line or lines to define part of said predetermined shapewhilst said sheet material remains supported by said first supportmeans, supporting said sheet material in a second position by a secondsupport means which is moved relative to said first support means, saidsheet material remains supported by said first support means cuttingthrough said sheet material by moving a line type cutter relative tosaid sheet material on a line or lines to define the remaining perimeterof said predetermined shape, to thereby cut said predetermined shapefrom said sheet material wherein in said second position said sheetmaterial is provided with upward support to support said predeterminedshape to be cut from said sheet material by said second support meansand wherein in said second position said first support means and secondsupport means includes a through hole commensurate to the line or linesto define the remaining perimeter of said predetermined shape.